home.md

@@ -4,18 +4,6 @@ Parabix technology is a high-performance programming framework for streaming
 text processing applications, leveraging both SIMD and multicore 
 parallel processing features.  
 
- * October, 2018: Unicode Level 2 support for regex matching under canonical and compatible (?K flag) equivalence 
- * September, 2018:  ICU 42 presentation on AVX-512/Parabix
- * June, 2018:  AVX-512 support for Parabix/icgrep 
- * June, 2018:  u32u8 application 
- * April, 2018:  File glob parsing using Parabix methods
- * May 2, 2016:  Check out the [wiki:ParabixOS ParabixOS] project!
- * November 18-20, 2015: Join us in Zhangjiajie, China for our presentation at [http://trust.csu.edu.cn/conference/ICA3PP2015/ ICA3PP 2015].
- * October 28-29, 2015:  Join us at the [http://llvm.org/devmtg/2015-10/ 2015 LLVM Developers' Meeting] for Parabix-LLVM discussion.
- * October 26-27, 2015:  Join us at [http://www.unicodeconference.org/ Unicode Conference 39] for our presentation of Unicode regular expression matching in icgrep.
- * September 2015:  Look at our plans for additional Parabix regular expression facilities in the [ParabixRegexRoadMap Parabix Regular Expression Road Map]
- * February 2015:  Check out [wiki:ICgrep icGrep] 1.0 offering [GigabytePerSecondGrep Gigabyte Per Second Performance]!
-
 ## Parabix Transform 
 
 The Parabix framework is based on the concept of parallel bit streams,
@@ -30,3 +18,22 @@ to process 128 code unit positions at a time.
 
 See the [Parabix Transform](ParabixTransform) page for details.
 
+## Alphabets, Character Classes, Unicode 
+
+The Parabix framework contains many facilities for working with character representations of various kinds.
+
+A fundamental notion is the character class bitstream.   This is a stream of bits in one-to-one correspondence
+with some input character code units, such that 1 bits indicate characters within the class and 0 bits indicate 
+characters outside of the class.  Often we use regular-expression notation to identify character classes,
+such as `[abc]` for the class containing the three lower-case letters "a", "b", and "c", and `[0-9]`
+as the class for decimal digits.   The following example shows an input character stream and the corresponding
+bit streams for the `[abc]` and `[0-9]` streams, respectively.   We conventionally mark 0 bits with
+periods (".") to make the 1 bits stand out.
+
+```
+input:   This is just 1 abbreviated example of character stream input containing 24 instances of the [abc] class and 6 instances of the [0-9] class. 
+[abc]:   ...............111....1......1........1.1.11........1........1...1.............1.1...........111..1.1...1.........1.1................1.1...
+[0-9]:   .............1..........................................................11..................................1...................1.1........
+```
+
+Read about the [Parabix Character Class Compilers](CharacterClassCompiler) for more information.
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